Releasable securing device



DeaIZ, 1944.

A. R; LUMSDEN 2,364,906

RELEASABLEJ SECURING DEVICE Filed March; 27', 1942 2 Sheets-Sheet l J, /0/ 4 a I 07 f/71 e/7 for /4//c/2 flaw/vie I Dec. 12, 1944.

Patented Dec. 12, 1944 UNITED STATES PATENT OFFICE RELEASABLE SECURING DEVICE Allen It. Lumsden, Los Angeles, Calif.

Application March 27, 1942, Serial No. 436,441

15 Claims.

This invention relates to securing or fastening devices and relates more particularly to releasable fastening means. A general object of this invention is to provide a simple dependable and effective releasable securing or fastening means.

The present invention is concerned with a securing means useful in'various situations. I will herein make reference to several forms of the invention as useful in securing removable doors, covers, fuselage sections, etc of aircraft, it being understood that this is a typical use or application and is not a limitation upon the usefulness of the invention.

Another object of this invention is to provide a fastening device that is extremely easy to install and operate and which may be readily released. The device of the present invention is merely inserted in place and the screw thereof is given a partial turn to complete the connection. The device is released by a partial turn of the screw whereupon the screw with the nut part or look part may be removed.

Another object of this invention is to provide a releasable fastening device which leaves an entirely clear flush outer surface on the structure on which it is employed and the fastening device is light in weight. These two features particularly adapt the device for use on aircraft.

Another object of this invention is to provide a releasable fastening device that embodies a resilient wire unit on one of the parts to be secured and a novel nut part or lock part on the screw cooperable with the wire unit to bend or flex the wire thereof and thus utilize the resiliency of the wire to hold the parts connected in tight engagement, the lock part being so constructed that it has no tendency to break or detach the wire unit in the event the parts are not accurately aligned or positioned. In prior devices of the same general nature there has been a distinct tendency for the wire unit to break or become permanently distorted and unfit for use in the event the wire unit is not accurately positioned with respect to the other unit of the fastening device. The present invention overcomes this disadvantage and there is little or no tendency for the wire unit to be broken or distorted in the event that it is not accurately positioned with respect to the other unit of the fastening means.

Another object of this invention is to provide a releasable securing means of the character referred to in which the wire unit may be replaced in the event that it is displaced or broken. In prior devices of this general nature it is often very difiicult, and sometimes impossible, to replace the wire unit when it is broken or lost.

Another object of this invention is to provide a releasable securing means of the character mentioned that may be readily adjusted or set to operate effectively where the parts to be connected are of different thicknesses. The nut part or look part may be adjusted along the screw to adapt the device for use on parts of different thicknesses.

A further object of this invention is to provide a releasable connecting "or securing means of the character mentioned in which the wire unit and the nut part or lock part have detent engagement which prevents the device from becoming loose or disconnected by vibrations, etc.

The various objects and features of my invention will be fully understood from the following detailed description of typical preferred forms and applications of my invention, throughout which description reference is made to the accompanying drawings, in which:

Fig. 1 is a fragmentary elevation View of the inner side of one form of releasable securing means of the invention and the parts connected thereby. Fig. 2 is an enlarged fragmentary vertical detailed sectional view taken as indicated by line 2-2 on Fig. 1. Fig. 3 is an enlarged fragmentary horizontal detailed sectional view taken as indicated by line 3-3 on Fig. 1. Fig. 4 is a View similar to Fig.' 1 illustrating another embodiment ofthe invention. Fig. 5 is an enlarged fragmentary vertical detailed sectional view taken as indicated by line 55 on Fig. 4. Fig. 6 is an enlarged fragmentary horizontal detailed sectional View taken as indicated by line ii6 on Fig. 4. Fig. 7 is an enlarged fragmentary elevation view of an alternative means for anchoring one end of the spring unit and Fig. 8 is an enlarged fragmentary detailed sectional view of the structure shown in Fig. 7' with the wire unit in place to be locked against displacement. Fig. 9 is a view similar to Fig. 2 wherein the parts are such that no reinforcement is needed.

In Figs. 1, 2 and 3 I have shown one form of the invention used with a supporting part, shell or body part which I will term a sheet It. The sheet Ill has an opening H which may be in the nature of an access opening, manhole, or the like, and an outer plate or cover i2 is provided to cover or close the opening I I. The cover I2 is adapted to lie flat against the outer surface of the sheet Hi. It is to be understood that the opening II and the cover [2 may be of substantial extent and that several releasable fastenside of the sheet ID, a stud or screw I4 carried by the cover I2 and passed through an opening in the sheet I0, and a nut or look part I on the screw I4 for cooperating with the unit I3.

The unit I3 presents or forms a flexible resilient latch or keeper element at the inner side of the plate or sheet I'll. Where the sheet I0 is formed of thin material or stock, as illustrated in Figs. 2 and 3, it is preferred to mount the unit on a reenforcing plate IS. The plate I 6 is rectangular and elongate for the reason which will later become apparent and is fixed against the inner or rear surface of the sheet Ill. Plate I6 has an opening O registering with the opening 0. The above mentioned opening 0 passes through the sheet I0 and its reenforcing plate I6. The opening 0 is elongated or of slot form and has an en largement I'I between its ends. The widened portion or enlargement I! of the opening 0 is preferably spaced midway between the ends of the opening and may be defined by cylindrically curved walls. The longitudinal axis of the elongate opening 0 extends longitudinally of the elongate plate I6 and the plate serves to reenforce that portion of the sheet I!) which is weakened to some extent by the provision of the opening 0.

When the sheet is thicker, as shown at Ill in Fig. 9, then the reinforcing plate I6 may be eliminated. In such case the structure would be as shown in Fig. 9.

The unit I3 includes anchors or posts I8 projecting from the rear surface of the reenforcing plate I6. The posts I8 are spaced beyond the opposite ends of the opening 0 and preferably lie in the longitudinal axis of the opening. In practice the posts I8 may be in the form of securing parts such as rivets and in accordance with the invention may serve to secure the reenforcing plate I6 to the sheet I0. Where the posts I8 are in the nature of rivets they have shoulders I9 bearing against the rear surfaces of the plate I6 and their heads'are set in the sheet III to lie flush with the outer surface of the sheet. The anchors or posts I8 have suitable heads 20 spaced from the rear surface of the reenforcing plate I 6.

The unit I3 further includes a pair of spaced flexible resilient arms or parts 2I spaced inwardly or rearwardly from the plate I6 and anchored by the posts I 8. The parts 2I are the active ele ments of the unit I 3, being engageable by the part I5. In the preferred construction the resilient parts 2| lie in substantially parallel planesand are in parallel relation to the longitudinal axis of the opening 0. The parts 2I are spaced outwardly or laterally beyond the sides of the elongate opening 0 occupying, planes which cross or are in tangent relation to the opening enlargement II.

In accordance with the preferred construction the resilient parts 2| are side portions of an elongated loop of wire or other suitable stock. This wire loop has portions 22 stepped or bent inwardly and has a reduced or curved closed end part 23 which engages on one of the posts I8. The closed end part 23 of the Wire loop is held in cooperation with the post I8 by its head 20. The wire at the other end of the loop has overlapping portions 24 which cooperate with the other post I8 and which are held on the post by the post head 20. If desired, the overlapping wire portions 24 may be soldered together or otherwise secured one to the other. It will be observed that the unit I3 has as its principal element a simple wire part that may be easily installed on the posts I8. The posts I8 serve to hold the wire loop structure where the parts 2| are in the proper parallel relation to the opening 0 and the stepped portions 22 serve to hold the resilient parts 2I in the correct spaced relationship to the rear surface of the reenforcing plate I6. As initially constructed and installed the resilient parts 2I lie substantially parallel with the rear face of the plate I6. In the preferred construction detent notches or depressions 25 are formed in the resilient parts 2|. The depressions 25 occur midway between the ends of the portions 2| to be at the enlargement I I of the opening 0 and maybe formed by bending the wire forming the parts 2 I.

It should be observed that the wire loop structure just described is formed and proportioned so that it may be passed inwardly through the opening 0 and then engaged on the posts I8 to occupy its operative position at the inner side of the sheet III. This is important as it provides for the ready replacement of a wire loop unit that may be displaced or broken. The loop is proportioned so that it may be readily passed through the opening 0 when arranged with its long axis substantially normal to the sheet III and with its transverse axis substantially parallel with the long walls of the opening 0. When the loop has been entered behind the sheet Ifi one end of the loop is engaged on a post I8 to be retained thereon by its head 20. The loop is then brought to a position where its opposite end portion ongages the head 20 of the other. The loop is then urged toward the sheet III with substantial force so that its engagement with the rounded head 20 causes slight elongation of the loop and the loop snaps over the head. This latches or engages the loop on said other post I8 and completes the replacement of the loop.

The screw I 4 serves to carry and actuate or control the lock part I5. The screw I4 may be a simple flush head type screw passed inwardly through an opening 26 in the cover I2 and adapted. to project through the opening 0 to extend a considerable distance rearwardly beyond the reenforcing plate I6. The opening 26 may be formed so that the head 2'! of the screw I4 lies flush with the outer surface of the cover I2.

The latch or look part I5 is carried by the screw I I to cooperate with the resilient parts 21 of the unit I3 to releasably hold the cover I2 in tight cooperation with the sheet It]. In this form of the invention the lock part I5 is a generally fiat elongate member carried in a diametric slot 28 in the screw I4. The slot 28 enters the rear-end of the screw I4 and is of substantial depth. The part I5 extends through the inner portion of .the slot 28, that is, the portion of the slot closest to the head 21 and projects radially from opposite sides of the screw. The rear edge of the part I5 may be straight. The forward edge of the part I5 is shaped to cooperate with and have latching engagement with the resilient parts 2|. As best illustrated in Fig. 2 of the drawings the forward edge of the lock part I5 has two pitched or sloping faces 29. The edges or surfaces 29 slope outwardly and rearwardly from adjacent the screw I4 and each surface 29 has a .detent notch 30 spaced between its ends.

in the forward edge of the lock part it.

'matic lateral adjustment of the lock part.

The notches 30 are ccoperable with the depressions. 25 to latch the part l in cooperation with the resilient parts 2|. A nut 3| is adjustably threaded on the screw 14 and is engageable with the straight rear edge of the lock part l5 to hold the lock part in the position for cooperation with the resilient parts 2| of the unit l3. The nut 3| is. provided with a series of circumferentially spaced openings 32 to receive a cotter key 33. The cotter key 33 may be passed through the pair of openings which register with the slot 28 and engages in the slot to hold the nut 3| against turning. It will be apparent how the nut 3| may be adjusted to the required position and then looked in place by means of the cotter key 33. With the construction just described it will be seen that the latch part or look part I5 is carried by the screw l4 to cooperate with the resilient parts 2| and to turn with the screw.

The invention provides means for holding the latch part or lock part. l5 against displacement from the screw l4, which means provides for limited movement of the lock part in directions both axially and radially of the screw so that the lock part will adapt itself to the resilient parts 2| and have correct engagement with the parts 2| even though the screw l4 may not be truly centered with respect to the unit is, This means includes a pointed or tapering wall 34 at the inner or forward end of the slot 25 and a complementa y tapering or V-shaped notch 35 The nut 3| may be set or locked in a position such as illustrated in the drawings where the lock part l5 has some axial play between the nut and the tapering slot wall. 34. This axial play allows the lock part I5 to shift transversely or radially with.

respect to the screw l4 so that the notches will come into correct cooperation with the depressions 25 even. though the screw I4 may not be equally spaced between the resilient. parts 2 l. The tapering wall 34 extending into the notch 35v prevents lateral detachment or displacement of the lock part I5 but permits the required auto- The sloping faces 2!! assist in directing the resilient parts 2| into the notches 3t.

It is believed that the operation of the securing means of Figs. 1, 2 and 3 will be readily under.- stood from the foregoing detailed description. When the plate or cover I2. is to be secured on the sheet ill the screw i4 is turned so that the lock part l5 can be passed inwardly through the opening 0. The screw l4 and the lock part l5 are passed inwardly to pass between the resilient parts 2| and to bring the cover l2 against the face of the sheet Ill. The screw M is then given a partial rotation or a turn of about 90. When this is done the lock part i5 is swung into 'cooperation with the resilient parts 2|, of the unit l3. When the part i5 is swung into cooperation with the resilientparts 2| the parts 2! are bent or flexed forwardly toward the plate i6 and when the lock part l5 assumes a position substantially normal to the resilient parts 2| the parts 2| snap .into the notches 3,0, that. is, the depressions. 25

of the resilient parts 2| cooperate with the notches 3d of the lock part iii. The resiliency of the flexed parts 2| urges the cover E2 inwardly and holds the cover tight against the face ofthe sheet Hi. It will be seen that the resiliency. of the parts 2| also serves to maintain the lock .part H3 in the latched position and the notches 30 and depressions 25 efiectively resist any tendency of the part l5 to turn. It is to be position that the lock part I5 is free to shift in the slot 28 through'its engagement with the resilient parts 2| and thus may accurately center itself with respect to the parts 2| in cases where the screw 4 is not equally spaced between the two lock parts. Thus, the shifting lock part l5 compensates for any slight misalignment there may be. To release the connection the screw I4 is merely turned about to disengage the lock part I5 from the resilient parts 2! and to bring the lock part into a position where it may pass out through the opening 0.

The form of the invention illustrated in Figs. 4, 5 and 6 may be said to comprise, generally, a resilient unit 49 at the inner side of the sheet H), a screw 4| on the cover l2 adapted to pass inwardly through an opening 42 in the sheet l0 and a latch part or lock part 43 on the screw 4| forcooperating with the resilient unit 40.

In Figs. 4, 5 and 6 it will be assumed that the sheet In is of heavier stock than in Figs. 1, 2 and 3 and that there is no need for a reenforcing'plate H5 at the opening 42. It is to be understood that the structure of Figs. 4, 5 and 6 may, if'desired or necessary, embody a reenforcing plate It. The opening 42, in the sheet l0 may be substantially the same as the opening 0 above described and, illustrated, is an elongate generally rectangular opening with an enlargement 44 intermediate its ends.

The unit All in this form of the invention includes two spaced flexible resilient parts 45 engageable by the latch part or look part 43. These resilient parts 45 extend substantially parallel with the long axis of the opening 42 and are spaced apart to lie in planes beyond the sides of the opening 42, which planes may intersect the opening enlargement 46, as illustrated. The resilient parts 45 constitute the spaced arms of an elongate generally U-shaped Wire element. There may be a single continuous length of wire or other suitable stock bent or shaped to have the spaced parts 45 and to he stepped downwardly or inwardly at the opposite ends of the parts 45 to have portions 46 which bear on the inner surface of the sheet Ill. The closed end portion 41. of the generally U-shaped wire member is shaped or bent to be pitched forwardly and toward the longitudinal axis of the screw 4|. The free ends of the wire are bent or shaped to have parts 48 which are likewise pitched forwardly and toward the 1021- gitudinal axis of the screw 4|. Openings 49 are provided in the sheet ill to receive the end portion 4! and the end parts 48 of the unit 4!]. The openings 49 are spaced beyond the opposite ends of the elongate opening 42 and are elongate or slot-like with their long axes transverse of the longaxis of the opening 42. The walls 50 of the opening 49 which lie nearest to the opening 42 are pitched or bevelled in the same direction as the end portion 4'5 and the end parts 48 of the wire unit 40. The closed end portion 41 and the free end parts 48 are verse of the long axis of the Opening 42. The resilient wire unit 40 is constructed and proportioned so that the portion 41 and end parts 48 cannot become displaced from the openings 49 during any normal use of the device. It is to be observed that the unit 40 may be introduced through the opening 42 and manipulated behind the sheet ID by a suitable tool to have its portion 41 and end parts 48 snap or latch into the openings 49. Thus, the unit 40 may be installed on the inner side of the sheet l from the front face of the sheet if this becomes necessary.

The stud or screw 4| serves to carry and operate the latch part 43. The screw 4| is passed inwardly through an opening in the cover l2 and has a shank 4| adapted to extend through the opening 42 and to pass rearwardly between the resilient parts 45. The head 52 of the screw 4| may be received in the opening 5| to lie flush with the-face of the cover l2.

The latch part 43 is carried by the screw 4| to cooperate with the resilient parts 45. The part 43 is in the nature of a block or nut threaded on the screw 4|. The part 43 is spaced inwardly or rearwardly from the head 52 to be behind the pa1ts-45 when the cover I2 is arranged in place against the sheet I0. Diametrically opposite wings 53 project from the latch part 43 for engagement with the resilient parts 45. The rear edges 54 of the wings 53 may be rearwardly convergent to assist in guiding the part 43 between the resilient wire parts 45. The forward edges of the wings 53 are shaped to cooperate and latch with the resilient wire parts 45. Notches or grooves 55 are provided in the forward edges of the wings 53 adjacent the hub of the latch part 43 to receive the wire parts 45. The leading corners of the wings 53 relative to the right hand diits wings 53 will cooperate with the resilient wire parts to flex the same forwardly when the latch part is turned behind the wire parts. In Fig. 5 of the drawings this means comprises a set screw or jamb screw 51 threaded in the outer end of the latch part 43 and adapted to clamp or jamb against the end of the screw 4| to lock the part 43 in the required position. In

the structure shown in Fig. 6 a jamb unit 58 is g.

threaded on the screw 4| to clamp against an end of the latch part 43 to lock or set the same in the required position. The lock or latch part 43 is set in an adjusted position where the engagement of its wings 53 with the resilient wire parts '45 will bend the wire parts forwardly when the latch part 43 is turned to its operative position.

It is to be understood that either cam or latch part l5 or 43 may be used in conjunction with either spring wire unit l3 or 40.

Figs. 7 and 8 of the drawings illustrate an alternative means for securing or anchoring the ends of the resilient wire unit on the sheet It). In this construction openings 49 are formed in the sheet similar to the openings 49. 6| spring from the front and rear faces, respectively, of the sheet I0 and project toward one another across the opening 49 The ears 6!) and SI are initially spaced apart a sufficient distance to allow the end portion 41 of the unit 40 Ears and to be engaged or hooked on the ear 6|. With the part 41 hooked on the ear 6| the part 60 is bent rearwardly to a position where it prevents the part 4'! from becoming disengaged from the ear 6|. It is to be understood that the structure shown in Figs. 7 and 8 of the drawings may be employed to anchor the unit l3, shown in Figs. 1, 2 and 3, and to anchor either or both ends of the unit 40 shown in Figs. 4, 5 and 6.

In the use or operation of the means illustrated in Figs. 4, 5 and 6 the latch part 43 is adjusted along the screw 4| to a position where its wings 53 will have the required engagement with the resilient parts 45 and the latch part 43 is set in the adjusted position by the set screw 51 or the lock nut 58. When the cover I2 is to' be secured on the sheet ID the screw 4| is turned to P sition the latch part 43 for ready passage through the opening 42 and the cover is brought against the sheet In to enter the lock part 43 through the opening 42 and to bring the lock part to a position behind the resilient wire parts 45. The screw 4| is then turned about so that the Wings 53 are brought to positions where they are transverse of the elongate opening 42. During this movement of the wings 53 the grooves 55 receive the spaced resilient wire parts 45 and the latch part 43 is so positioned that this engagement results in forward fiexure of the wire portions with a resultant rearward force exerted on the screw 4| to hold the cover l2 tight against the sheet ID. It should be observed that in the event the screw 4| is not accurately centered between the resilient wire parts 45 that the engagement of the pitched surfaces and the grooves 55 with the wire parts 45 may result in a lateral shifting of the unit 40 to bring the unit to a position where it is centralized with respect to the screw 4| and latch part 43. When it is desired to release or remove the cover 2 the screw 4| is turned about 90 to swing the wings 53 free of the resilient wire parts 45, whereupon the cover |2 may be moved outwardly to move the lock part 43 outwardly through the opening 42.

Having described typical preferred forms and applications of my invention, I d not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any variations or modifications that may appear to those skilled in the art or fall within the scope of the following claims.

Having described my invention, I claim:

1. A releasable fastening means for securing two members together, one member having an opening, said means comprising a turnable stud on the other member adapted to pass through said opening and two cooperable latch parts, one aresilient unit on the member which has said opening, the other a latch part carried by the stud to project laterally therefrom and to be inserted through the opening with thestud and turnable with the stud, one of said parts being supported for bodily lateral movement relative to said opening so that said parts are related for relative bodily movement in a lateral direction to assure correct latching cooperation of said parts when the latch part is turned into engagement with the resilient unit.

2. A releasable fastening means for securing two members together, one member having an opening, said means comprising a turnable stud on the other member adapted to pass through said opening and two cooperable latch parts, one a resilient unit mounted on the inner side of the member which has said opening, said unit havturnable with the stud and adapted to be passed through said opening and between said portions to latch with said portions upon turning of the stud, one of said parts being bodily shiftable in a lateral direction relative to the stud whereby said parts automatically assume the correct relationship when the latch element is turned into cooperation with said spaced portions.

3. A releasable fastening means for securing two members together, one member having an opening, said means comprising a turnable stud on the other member, resilient means adapted to be passed through the opening to a position behind the member which has the opening, means on the member which hasthe opening for removably anchoring the resilient means thereon, the resilient means including spaced parts at opposite sides of the axis of the opening, a latch part carried by the stud to project laterally therefrom and to be inserted through the opening with the stud and turnable with the stud adapted to be passed through said opening and through the space between said parts and turnable into latching cooperation with said parts, and means at the stud whereby the position of the latch part along the studs can be adjusted by rotating the stud.

4. A releasable fastening means for securing two members together, one member having an opening, said means comprising a turnable stud on the other member, resilient means at the back of the member which has the opening, the resilient means including a part at each side of the aXis of the opening, a latch part carried by the stud to project laterally therefrom and to be inserted through the opening with the stud and turnable with the stud adapted to be passed through said opening and through the space between said parts and turnable into latching cooperation with said parts,-and means holding the resilient means in place at the back of the member with the opening so it is bodily shiftable relative to said members to be automatically centralized relative to the latch part when engaged by the latch part.

5. A releasable fastening means for securing two members together, one member having an opening, said means comprising a turnable stud on the other member, resilient means at the back of the member which has the opening, the resilient means including a part at each side of the axis of the opening, a latch part carried by the stud to project laterally therefrom and to be inserted through the opening with the stud and turnable with the stud adapted to be passed through said opening and through the space between said parts and turnable into latching cooperation with said parts, and a projection on the member having the opening to receive and hold said latch part so it is shiftable laterally relative to the stud to automatically centralize itself when turned into engagement with the first named parts.

6. A releasable fastening means for securing two members together, one member having an opening, said means comprising a turnable stud on the other member, resilient means on the member which has the opening, the resilient means including a single length of wire adapted to be passed through said opening to the rear side of the member which has the opening, means for anchoring the resilient means on the rear side of said member to have a part at each side of the opening, the anchoring means being releasable to permit replacement of the resilient means, a latch part carried by the stud to project laterally therefrom and to be inserted through the opening with the stud and turnable with the stud adapted to be passed through said opening and through the space between said parts and turnable into latching cooperation with said parts, and means threaded to the stud to adjust the latch part along the stud.

7.,A releasable fastening means for securing two members together, one member having an opening, said means comprising a turnable stud on the other member, resilient means adapted to be passed though said opening to a position behind the member which has the opening, the resilient means including an elongate loop of wire having longitudinal side parts, means on the member which has the opening for engaging in the ends of the loop to replaceably anchor the loop on said member where said side parts extend at opposite sides of said opening, the anchor means at one end of the resilient means allowing the resilient means to shift laterally, a latch part carried by the stud to project therefrom and turn therewith and adapted to be passed through said opening and through the space between said side parts and turnable into latching cooperation with said side parts, and means for adjusting the latch part along the stud. i i

8. A releasable fastening means for securing two members together, one member having an opening, said means comprising a turnable stud on the other member, resilient means on the member which has the opening, the resilient means including a part at each side of the opening, said stud having a transverse slot, and a latch part in said slot movable into latching cooperation with said parts upon turning of the stud.

9. A releasable fastening means for securing two members together, ne member having an opening, said means comprising a turnable stud on the other member, resilient means on the member which has the opening, the resilient means including a part at each side of the opening, said stud having a transverse slot, and a latch part in said slot movable into latching cooperation with said parts upon turning of the stud, the latch part being shiftable in the slot to centralize itself relative to said parts.

10. A releasable fastening means for securing two members together, one member having an opening, said means comprising a turnable stud on the other member, resilient means on the member which has, the opening, the resilient means including a part at each side of the opening, said stud having a transverse slot, a latch part in said slot movable into latching cooperation'with said parts upon turning of the stud, and means for adjusting the latch part longitudinally of the stud.

11. A releasable fastening means for securing centralize itself relative to said parts, and means for adjusting the latch part longitudinally of the stud.

12. A releasable fastening means for securing two members together, one member having an opening, said means comprising a turnable stud on the other member adapted to pass through said opening and two cooperable latch parts, one a resilient unit on the member which has said opening, said unit having a pair of spaced portions behind said opening, the other part being a latch element turnable with the stud and adapted to be passed through said opening and between said portions to latch with said portions upon turning of the stud, one of said parts being shiftable ina lateral direction relative to the stud whereby said parts automatically assume the correct relationship when the latch element is turned into cooperation with said spaced portions, and

14. Means for releasably securing an outer member to an inner member, the inner member having a slot and openings spaced from opposite ends of the slot, said means comprising a turnable stud on the outer member, a resilient means on the inner side of the inner member comprising a length of wire of generally U-shape having its ends anchored in said openings and having its side parts at opposite sides of the slot, and a latch part on the stud adapted to be passed through the slot and turnable into latching cooperation with said side parts.

15. Means for releasably securing an outer member to an inner member, the inner member having a slot and openings spaced from opposite ends of the slot, said means comprising a turnable stud on the outer member, a resilient means on the inner side of the inner member comprising a length of wire of generally U-shape having its ends anchored in said openings and having its side parts at opposite sides of the slot, and a latch part on the stud adapted to be passed through the slot and turnable into latching cooperation with said side parts, the ends of the wire being shiftable in said openings so that the unit will centralize itself relative to the latch part.

ALLEN R. LUMSDEN. 

